THIS year, for the first time, glatt kosher food will be sold at the Super Bowl.

Certainly, faith will prompt some of the fans at Dolphin Stadium in Miami Gardens, Fla., to line up at one of two carts selling grilled salami sliders and garlicky knoblewurst. But for others, the appeal of a kosher hot dog will have nothing to do with religion.

In an era of heightened concern over food contamination, allergies and the provenance of ingredients, the market for kosher food among non-Jews is setting records.

Only about 15 percent of people who buy kosher do it for religious reasons, according to Mintel, a research group that last year produced a report on the kosher food explosion. The top reasons cited for buying kosher? Quality, followed by general healthfulness.

“It’s keyed into the issues of food safety and consumer fear,” said Larry Finkel of Packaged Facts, a consumer market research company that also released a study last year on the growing market for kosher foods. “The reputation of kosher is stretching beyond chicken, whether there is truth to it or not.”

Most people who buy kosher because they think it’s safer or more healthful are likely not well versed in the complex set of ancient Jewish dietary laws that include, among other things, rinsing blood from carcasses with salt and water, never mixing meat and dairy, and allowing fin fish but not shellfish.

The non-Jewish kosher market has been growing in earnest since the 1990s, when the koshering of the Oreo was hailed as a watershed event and ConAgra Foods bought the Hebrew National hot dog brand. Now, 40 percent of the food sold at grocery stores has a kosher imprint, according to the kosher and halal food initiative, a research project at Cornell University.

Recently, the pace has picked up. Major retailers including Wal-Mart, Costco and Trader Joe’s have kosher programs. At FreshDirect, the New York City grocery delivery company, orders for kosher chicken were up 30 percent in 2009. The kosher Tootsie Roll was introduced last month.

Because so many packaged foods carry a kosher seal, shoppers unwittingly buy kosher food every day. But people who buy products specifically because they are labeled kosher could be spending as much as $17 billion by 2013, according to Packaged Facts.

At Mississippi State University, Prof. Yvonne Vizzier Thaxton added ritual halal and kosher slaughter to her poultry science syllabus after she realized it was a niche that should not be ignored by conventional poultry processors.

She is not convinced that salting and other steps involved in koshering produce better chicken than conventional methods, but a few years ago she started to notice a marked increase in the number of people who do believe it. The industry, she said, needs to take a good look at the potential for growth.

“We’ve been too narrow in our perspective,” she said.

Some shoppers who were not raised in kosher families use the label as a stand-in for other signifiers. “I prefer to buy local and organic, but when I get to the market late and they have sold out of the chicken, I end up buying kosher because I feel it is the second-best thing,” said Myra Kohn, a food blogger in Seattle who goes by the digital pen name Seattle Bon Vivant.

For some shoppers, kosher means purity of ingredients. Vegetarians know a parve label means absolutely no meat or dairy products. (Vegans, though, are out of luck. Parve food can contain eggs and honey.)

Families with food allergies like the increased availability of kosher products for a similar reason. Bryan Adams is an entertainment publicist from Teaneck, N.J., whose son had terrible skin problems when he was born. A holistic medical adviser suggested the family cut out a number of foods, including soy and gluten. The child’s skin cleared, and Mr. Adams discovered his own gluten intolerance.

Now, the family stocks the kitchen with certain brands of kosher mayonnaise and margarine that aren’t made with ingredients that trigger outbreaks.

Nosheen Nazakat, a Muslim from Pakistan, often buys kosher when she cannot find halal food. She is also a discerning cook who is happy to browse the aisles at Pomegranate, a 20,000-square-foot store in Midwood, Brooklyn, whose fans call it the kosher Whole Foods.

The neighborhood is home to several large Orthodox synagogues and the largest mosque in the borough.

Although Pomegranate sells dry-aged prime steaks for $36.99 a pound, pristine marrow bones and rows of whole chickens, Ms. Nazakat buys all her meat from the halal butcher a few blocks away. But the salads, the fresh hummus and the olive bar?

“Very, very good,” she said.

Increasingly, a certain brand of non-Jewish gastro-tourists are making their way to the store as well.

“On Sundays, we call it visiting day,” said Mike Steigman, who is in charge of Pomegranate’s three kitchens — one each dedicated to meat, parve and dairy preparations. “A lot of Park Slope, no matter what their background is, comes that day.”

Neil Glick, a real estate agent active in local Washington politics, was raised in a mixed Reform and Conservative household that didn’t keep kosher. But after reading books and watching films that depicted horrific examples of conventional slaughterhouses, he was essentially scared kosher — at least when it comes to meat.

“One thing about kosher food — I do feel less guilt in eating it because I know the end was not as cruel,” he said.

That point is debatable. Certainly, humane treatment is built into Jewish dietary law. Animals must be handled with care, fed a specific diet and slaughtered with a swift cut to the carotid artery. (In addition, rabbis inspect carcasses for defects like broken bones or infection. Washings in salt and cold water help remove all traces of blood.)

The cattle expert Temple Grandin has worked extensively with some large kosher processors to develop humane standards. But some experts in animal welfare warn consumers not to assume that kosher means humane. (Animals slaughtered in accordance with religious law are an exception written into the federal Humane Methods of Livestock Slaughter Act, which requires that mammals be stunned unconscious before killing.)

“Like anything else, it depends on the management and the quality of the operation and the training of the personnel,” said Adele Douglass of Humane Farm Animal Care. The group certifies processors like Applegate Farms and Murray’s Chicken, which meet its strict standards of humane treatment and slaughter. It certifies one halal poultry producer who stuns chickens after throat slitting, but has had no kosher producers who have asked to complete the program.

Ms. Douglass and others point to Agriprocessors, once the largest kosher meatpacking plant in the United States, as an example of what can go wrong. The company filed for bankruptcy in 2008 amid charges of labor abuse and inhumane treatment of animals.

Science is mixed when it comes to the relative safety of kosher meat, said Carl Custer, a former federal Agriculture Department microbiologist.

In 2007, researchers at the Agriculture Department infected chicken skin with salmonella. Then they applied kosher salt and rinsed the skin, measuring pathogen levels along the way. Salt alone didn’t reduce contamination, but the combination of salting and rinsing reduced salmonella levels by 80 percent.

That same year, another study of 353 whole or cut raw chickens offered different results. Agriculture Department researchers compared conventional, kosher and organic chickens. The conventional chicken had the least amount of total contamination. The organic poultry had the most salmonella, the conventional poultry the most campylobacter and kosher the most listeria.

As far as taste, the jury remains out. Anyone who has ordered a kosher meal on a plane can tell you there is plenty of unappealing kosher food in the world. And an Oreo tastes like an Oreo, whether a rabbi supervised its creation or not.

Still, cooks like Christopher Kimball, who founded Cook’s Illustrated magazine, swear by the juiciness of Empire Kosher birds. And a whole chicken from Kosher Valley, a new, antibiotic-free kosher brand from the Hain Celestial Group, a natural and organic food producer, made for a delicious dinner roasted with fresh fennel and lemon.

The Kosher Valley chickens are raised on vegetarian feed in Pennsylvania and processed in upstate New York. Priced as much as 40 percent less a pound than organic kosher chicken, they’ve been a good seller at Whole Foods, which began offering them late last year. “This new line brings it to a more affordable price point, so kosher has become an option for everyone,” said Jim Zola, a Whole Foods regional meat coordinator.

Not every expert on the Jewish market buys the reasons behind the growth of kosher food. Elie Rosenfeld is the chief operating officer of the New York firm Joseph Jacobs Advertising, which helped introduce Rebecca Rubin, the first Jewish doll in the American Girl line.

He doesn’t disagree that kosher food is growing more popular, especially among higher-end cooks and chefs. But he doesn’t think it is a mass movement and believes food companies continue to expand their kosher lines to serve the Jewish community, not to capture the nonkosher consumer.

“It’s an unexpected side benefit to a certain extent, but the volume is there for people who keep kosher,” he said.

Why quibble over why, said Yaakov Yitzchak Horowitz, the Manischewitz company rabbi and director of its kosher development operations.